This thesis argues that unfair social disadvantage is best conceived as the relative impairment of the will of the person when that will is directed towards a valuable end. That valuable end is self-realisation. The term ‘self-realisation’ signifies a perfectionist conception of social justice in which the self-realisation of other persons forms part of one’s own self-realisation. Although the notion of a substantive will is taken to be illusory, the experience of will is taken to be as real as the experience of pain. The experience of will is therefore taken to be the de facto will. It is argued that the will extends beyond the mind of the individual to include the culture, technology, and circumstances of the person’s environment. This conception of the will connects social disadvantage and morality within a framework of capabilities. It is then argued that social disadvantage can be mitigated by application of a principle of will-egalitarianism: the idea that all persons ought to have an equal opportunity to exercise will compatible with a similar scheme for all. This scheme is sufficientarian, but one in which a lower threshold of sufficiency of the will is tracked by an upper threshold. This upper threshold represents the degree of realised will above which persons cannot progress further towards self-realisation in the presence of others below that threshold. The thesis concludes with a discussion of the significant implications (both practical and theoretical) for the role of the state. These include the adoption of policies designed to empower individuals, rather than targeting the circumstances of disadvantage. Such an approach would support policies that enhance social mobility, public participation, and the breaking down of social and class barriers, whilst addressing some of the problems associated with a ‘benefits culture’.